Earlier this year, the morning skies above Chelyabinsk lit up as a meteor streaked across the sky, detonating in the atmosphere with a concussive explosion that shook buildings, set off car alarms, and shattered windows.

In January, a month before the meteor loudly announced its entry in Earth's atmosphere above the Ural Mountains, Chelyabinsk's native son Sergey Kovalev underlined his emergence as a major contender in the light-heavyweight division with a three-knockdown, third-round stoppage of former beltholder Gabriel Campillo. Prior to that, Campillo had not been stopped in almost six years. But Kovalev, who makes his HBO debut on Saturday against Britain's Nathan Cleverly, left no doubt.

It was, the Russian tells HBO.com, the fight that "brought me the most attention and notoriety" among boxing fans. But it was merely the culmination of a boxing career that began in December 1994 when, as an 11 year old, he walked into a boxing gym next to a cinema behind the Chelyabinsk Tractor Plant. That led to an amateur career that brought gold, silver and bronze medals at national championships, gold medals at World Military Games and a reported amateur record of 193-22. In 2009, not enamored of his opportunities in his home land, he moved to the United States to pursue a professional career.

After an unhappy spell in North Carolina ("I had a feeling of being alone in a strange country," he says), he moved to Los Angeles, hooking up for a while with Abel Sanchez – formerly chief second for Hall-of-Famer Terry Norris and now for Gennady Golovkin – before ultimately settling with middleweight champ-turned-trainer John David Jackson.

The four fights to date that he has worked with Jackson have coincided with perhaps the most impressive run of his career, with none of his opponents in that time lasting past three rounds. Part of that, says Kovalev, is that as the level of opposition has increased, "I can show my boxing skills." Part of it also is the evident comfort level he enjoys with Jackson.

"The beauty with Sergey is, the first day he gets to camp, I tell him what I'm thinking and he tells me what he's thinking, and he comes up with a plan," Jackson says. "From that point on, I don't really mess with him, because as the weeks progress, he's working on it. I might just add small things to his game, because he knows how to fight. We work real well together, because I let him do what he likes to do best."

Discussion of Kovalev's record inevitably focuses on the fact that his 21-0-1 record includes 19 KO's. But, says Kovalev, he doesn't enter the ring with the intent to knock out his opponents: it just happens. "I never felt like I was a Superman in boxing," he shrugs. "I don't even know how to describe it."

Jackson, however, does.

"He knocks people out because he sets them up a certain way," he says. "He has a great boxing style because his foot is always right, and he plants it really well before he throws punches. That doesn't happen because he's lucky."

"He's a really intelligent fighter. He just hasn't had the chance to show the public how intelligent he is, because he's been knocking people out by the third round, and honestly I wouldn't care if he never got the chance to show his true boxing skill. But one day he will. He'll face a guy who can take his punch pretty well, and he'll have to rely on his boxing skills to win the fight."

That day may come on Saturday against Cleverly, a skilled boxer with a high punch output who holds a world title belt, and who, like Kovalev, is undefeated. It stands to be by far the toughest test of his career, and Cleverly's backers are confident of upsetting the apple cart.

But Kovalev, while recognizing the magnitude of the task in front of him, sees it as an important bridge to the next phase of his career, one that he hopes results in him not only moving to another level but also staying there long enough to make his mark. It is, after all, one thing to be a meteor that streaks across the sky, leaving an impression but soon disappearing forever; it is another entirely to be a star that shines for years to come.